Many work vehicles, including construction work vehicles and agricultural work vehicles, perform functions that reduce the stability of the work vehicles with respect to the ground. For example, a construction vehicle such as a loader-backhoe can perform the function of digging a hole using a boom assembly attached to the rear of the loader-backhoe. As the boom assembly digs into the ground, force (and torque) is applied to the loader-backhoe tending to cause the loader-backhoe to be lifted off of the ground. Further, as the boom assembly lifts dirt (or other material) out of the ground, force is applied to the loader-backhoe in the opposite direction (and torque is applied tending to cause the front of the loader backhoe to tilt upwards). Additionally, lateral forces (and torques) are experienced by the loader-backhoe as the boom assembly is moved with respect to the loader backhoe, tending to cause the loader-backhoe to shift its position in relation to the ground. For at least these reasons, the application of such forces (and torques) upon the loader-backhoe tend to destabilize the loader-backhoe.
Because the performance of such functions by work vehicles tends to reduce the stability of the work vehicles, many of such work vehicles are equipped with support assemblies including support leg assemblies and stabilizer flip pad assemblies. Such support assemblies are designed to increase the stability of the work vehicles from what it would otherwise be if the work vehicles were supported only by wheels (or tracks, etc.) with respect to the ground. The support assemblies provide additional points of contact with the ground over which the forces experienced by the work vehicles are distributed. In addition, the support leg assemblies of the support assemblies of a work vehicle (when in operation) typically extend outwards from the body of the work vehicle. Consequently, the torques experienced by the work vehicle are less likely to produce movement of the vehicle. Further, the support assemblies provide more friction with respect to the ground, reducing the tendency of the work vehicle to shift laterally.
Such support assemblies on work vehicles, however, are only effective if the support assemblies have effective traction with respect to the ground. Thus, support assemblies typically include feet or pads at the bases of the support leg assemblies, which interface the ground. The pads are typically rotatable so that they can interface the ground at a variety of angles despite variation in the slope of the surface of the ground. Further, the pads typically have two different types of support or interface surfaces on opposite sides of the pads, for interfacing different types of ground surfaces. Typically, each pad has a first surface that is a cleat surface, for interfacing dirt or rocky soil, and also has a second, rubber surface (on the opposite side of the pad) that is for interfacing concrete or blacktop (or other smooth surfaces). Because the pads are rotatable, the pads can be rotated (or flipped) so that either the first or second surface will interface with the ground (hence, the pads are referred to as "stabilizer flip pad assemblies").
For maximum traction, it is important that the proper interface surface of a stabilizer flip pad assembly be in contact with the ground. Nevertheless, it is common that during the operation of a work vehicle a stabilizer flip pad assembly inappropriately rotates such that the wrong interface surface of the stabilizer flip pad assembly is in contact with the ground. An operator typically will carefully position a stabilizer flip pad assembly while the support leg assembly (to which the stabilizer flip pad assembly is attached) is in a raised position off of the ground so that, when the support leg assembly is lowered, the proper surface of the stabilizer flip pad assembly will interface the ground. However, due to forces encountered by the work vehicle while the support assembly is in the air (as well as due to forces generated by the motion of the support assembly itself), the stabilizer flip pad assembly can further rotate even after its position has been set by the operator, such that the stabilizer flip pad assembly is in the wrong position by the time the support assembly is fully lowered to the ground. Such undesirable rotation is especially common if the different interface surfaces of the stabilizer flip pad assembly are differently-weighted such that the stabilizer flip pad assembly has a tendency to rotate to a particular position due to gravity.
In addition, a stabilizer flip pad assembly can rotate to an improper position even when the support assembly to which the stabilizer flip pad assembly is attached is in use (i.e., while the support assembly is lowered to the ground). Due to the forces (and torques) experienced by a work vehicle (which can cause the vehicle to bounce up and down on the ground), there are times when a stabilizer flip pad assembly can lift off of the ground and rotate unexpectedly (while in the air).
If the stabilizer flip pad assembly rotates so that the proper interface surface is no longer positioned to interface the ground, the traction of the work vehicle with respect to the ground will be compromised. Various systems are currently known for limiting the amount of rotation of stabilizer flip pad assemblies, including rubber or neoprene restraints (which deflect under load). However, such rubber and neoprene restraints are often unreliable in limiting the rotation of the stabilizer flip pad assemblies, and are quickly worn out in the harsh environments in which work vehicles are typically operated.
Accordingly, it would be advantageous to develop a new apparatus and method for limiting or controlling the rotation of stabilizer flip pad assemblies to prevent undesired flipping of the stabilizer flip pad assemblies. Further, it would be advantageous to develop such an apparatus and method for limiting the rotation of stabilizer flip pad assemblies that is highly reliable in its operation, and is durable. Additionally, it would be advantageous to develop such an apparatus and method that is simple to operate, and simple and inexpensive to manufacture.